This table lists the meta-characters understood by the WhatsUp Gold Regex Engine.
Meta-character  | 
Matches  | 
|
  | 
dot  | 
Matches any one character  | 
  | 
character class  | 
Matches any character inside the brackets.  | 
  | 
negated character class  | 
Matches any character except those inside the brackets.  | 
  | 
dash  | 
Used within a character class. Indicates a range of characters.  | 
  | 
escaped character  | 
Interpret the next character literally.    | 
  | 
binary character  | 
Match a single binary character. nn is a hexadecimal value between 00 and FF.  | 
Meta-character  | 
Matches  | 
|
  | 
question  | 
One optional. The preceding expression once or not at all.  | 
  | 
star  | 
Any number allowed, but are optional.  | 
  | 
plus  | 
One required, additional are optional.  | 
  | 
  | 
"Non-greedy" versions of ?, +, and *. Match as little as possible, whereas the "greedy" versions match as much as possible  | 
Meta-character  | 
Matches  | 
|
  | 
caret  | 
Matches the position at the start of the input.  | 
  | 
dollar  | 
At the end of a regular expression, this character matches the end of the input.  | 
Meta-character  | 
Matches  | 
|
  | 
alternation  | 
Matches either expression it separates.   | 
  | 
parentheses  | 
Provides grouping for quantifiers, limits scope of alternation via precedence.  | 
  | 
backreference  | 
Matches text previously matched within first, second, etc, match group (starting at 0).  | 
  | 
negation  | 
The expression following ! does not match the input  | 
Abbreviations are shorthand Meta-characters.
Abbreviation  | 
Matches  | 
  | 
Any alphanumeric character: ([a-zA-Z0-9])  | 
  | 
White space (blank): ([ \\t])  | 
  | 
Any alphabetic character: ([a-zA-Z])  | 
  | 
Any decimal digit: [0-9]  | 
  | 
Any non decimal digit: [^0-9]  | 
  | 
Any hexadecimal digit: ([0-9a-fA-F])  | 
  | 
Newline: (\r|(\r?\n))  | 
  | 
Any punctuation character: ,./\';:"!?@#$%^&*()[]{}- _=+|<>!~  | 
  | 
Any non-punctuation character  | 
  | 
A quoted string: (\"[^\"]*\")|(\'[^\']*\')  | 
  | 
WhatsUp Gold style white space character: [ \\t\\n\\r\\f\\v]  | 
  | 
WhatsUp Gold style non-white space character:  | 
  | 
Any word characters (letters and digits): ([a-zA-Z0-9_])  | 
  | 
Non-word character: ([^a-zA-Z0-9_])  | 
  | 
An integer: ([0-9]+)  |